(Scott Olson and Joshua Steffan) When tuning a database environment such as DB2, the Database Administrator (DBA) often needs to look at many things on many different levels before determining a viable approach to resolving the issue at hand. Is the application SQL written properly? Are the database

(Knut Stolze) DB2 Universal Database supports offers several built-in aggregate (or column) functions including AVG, COUNT, MIN, MAX, SUM, and others. However, there is currently no direct way to implement your own user-defined aggregate function. This article presents an approach for achieving spec

(Alex Jarzebowicz) The no-charge IBM DB2 UDB Migration Toolkit can simplify and improve your migration to DB2 Universal Database (DB2 UDB). This migration utility provides a wizard and an easy-to-use interface with only five steps to help you quickly convert existing Sybase, Microsoft SQL Server, Or

(Essma Hasin) IBM DB2 V8.1 is a great new release with numerous new enhancements in terms of engine capabilities, such as MDC (multi-dimensional clustering) and online reorg to name a few, as well as great new tools such as the Health Center, the Development Center, and the Development Add-Ins for M

Developing applications that access both Web services and database management systems can be an overwhelming task. It doesn’t need to be. This tutorial demonstrates how to generate DB2 user-defined functions (UDFs) that provide access to Web services. The generated UDFs can be used in SQL statements

(Alexander Kuznetsov) When an index contains all the columns involved in a query, we usually say that an index covers a query. Whenever, this happens, the DB2 optimizer usually chooses to access only that index to satisfy a query, which is called index-only access or index covering. “Usually” does n

(Roger Sanders) In my previous columns, I showed how certain registry variables and configuration parameters influence the performance of DB2 Universal Database (UDB) for Linux, Unix, and Windows. In this column, I’ll tackle another factor that can have a significant impact on database performance:

This article provides some great questions (and the associated answers) that you can ask of potential hires during the interview process.

(Paul C. Zikopoulos and Roman B. Melnyk) Today’s databases (and especially data warehouses) have become so large, and their query workloads have become so complex, that it is often impractical and even unnecessary to retrieve all of the data that may be relevant to a particular query. Rather than us

(Craig S. Mullins) Visual Explain is a phenomenal tool in IBM® DB2® Universal DatabaseTM that can be used by programmers and DBAs to detail the access paths chosen by the DB2 optimizer for SQL statements. Indeed, Explain should be a key component of your performance monitoring strategy. The informat